


You are the father

by JessicaTrumen



Category: One Piece
Genre: Alternate Universe - Canon Divergence, Fluff and Humor, M/M, Mpreg, Portgas D. Ace Lives
Language: English
Status: Completed
Published: 2021-01-01
Updated: 2021-01-01
Packaged: 2021-03-10 23:02:14
Rating: Teen And Up Audiences
Warnings: Underage
Chapters: 1
Words: 4,763
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28475106
Author URL: https://archiveofourown.org/users/JessicaTrumen/pseuds/JessicaTrumen
Summary: WARNING: Pregnant Luffy who is 17One step away from finally revenging Thatch's near death, Ace encountered Marco who successfully persuaded him to go back with the following words."Your brother is pregnant and you are the father."
Relationships: Monkey D. Luffy/Portgas D. Ace
Comments: 12
Kudos: 139





	You are the father

**Author's Note:**

> I steeled myself to re-watch Marineford arc, but still cried my eyes out. So here I am, bringing myself some comfort.
> 
> Ace, happy birthday and stay alive at least in this fic! Don't you dare make Luffy cry again.

When Garp burst through the door, he expected to see a lot of things on his grandson's face. But as the unpredictability ran in the Monkey family's bloodline, he got nothing he had expected.

Upon seeing his face, Luffy vomited his guts out after muttering "Grandpa" . The first thought emerged in Garp's mind is"Last time I checked, I'm not disgusting but good-looking", before he was engulfed by fear.

LUFFY VOMITED?! NO WAY!

The kid's stomach had the capacity of black hole and the toughness of Impel Down, and he never vomited! Garp panicked, and everyone else in this room did the same, if the collective silence of many seconds was anything to go by.

A cat-like creature shrilled:"Doctor, we need doctor! Wait, I'm a doctor! ", which snapped everyone out of the shock.

Next thing he knew, the green-haired swordman took the first mate's responsibility, assigning tasks. 

The sniper and the cook cleaned up the mess, the navigator and archaeologist gave him the overdue welcome. The first mate himself supported his paled captain walking to the bed with the blue-nosed doctor hot on his heels.

Garp had got to admit that his grandson's crew was not bad.

Right Now, everyone gathered around the bed awaiting, while the cat that turned out to be a reindeer ran some test. 

Suddenly, his furry face had this weird expression on it, and he said something that stole people's breath away:"Guys, I think we need to send him to hospital."

He added:"Just to be sure."

That's how they found themselves in the nearest hospital, having their eyeballs bulged out of the sockets.

They shouted out in unison:"What do you mean by he is pregnant!!"

The doctor seemed to be quite familiar with the situation. After all , the most of male carriers didn't know what they were capable of until they were pregnant. He repeated himself :"The results suggest that the patient is a male carrier and about three months pregnant."

The said patient cupped the non-existent bump on his abdomen, giving it his trademark wide smile:"Shishishishi, so cool, I've got to tell Ace."

The mention of Ace sent some of strawhat crew into a panic attack. Luffy's brother told them to take care of him. And now, he ended up pregnant right under their noses. A fire fist targeted at them is on its way!!!

Being non-characteristically gentle, Garp asked his grandson:"Luffy, is it bad touch?"

Everyone waited for the answer. Zoro was even ready to draw his swords.

"Nope."

Everyone found comfort in his word, but suspicion remained. What if the boy didn't even know what a bad touch is?

Garp continued:"Then how did you get pregnant?"

Luffy looked around, and they all seemed to be oblivious to the evident answer. While, he knew a dumbass when he saw one. He puffed out his chest:"It's very simple, I had sex!"

"NOOOOOOOOOOOO!"

Here went the scream.

Looked at Luffy's face, who could put his name and sex in the same sentence! And he just claimed that he didn't only know about sex but also learned it firsthand.

Usopp whispered:"That's the scariest thing I' ve ever heard."

Fresh out of his mental breakdown, Garp added one more reason on his "Why I hate Shanks list". Just look what the bad influence Redhair brought upon Luffy had done: Luffy was a pirate and pregnant out of wedlock being 17!

"So who is the bastard that knocked you up?" Garp said through gritted teeth.

Luffy was apparently unfazed by the tense atmosphere. He just took off his straw hat, fishing out the Vivre Card and staring at the direction it indicated:"Ace. Where is Ace. Shishihsishi, I can't wait to tell him."

Not getting the answer, Garp waved his hand:"Luffy, answer my question, then I will tell Ace the news for you, lest he didn't know who he should burn alive. "

While saying the last part, Garp made sure to give the male members of strawhat crew an intimidating look.

Everyone on the receiving end of that look broke a sweat. At the same time, Luffy's brain apparent couldn't handle this amount of implication.

"Who will be burned by Ace?"

Garp shook his clenched fist:"That actually depended on your answer". Noticing the confusion on Luffy's face, he sighed and chose to be straight forward:"Basically, whoever made you pregnant. And who is he?"

"I already told you the answer, dumbass grandpa, and why would Ace wanna burn himself?" Luffy tilted his head.

Silence.

Put two and two together, the answer dawned on them. The calm before storm disappeared with Garp's roar:"ACE!!!"

How did this happen? Ace silently questioned himself.

One hour ago, Ace was in a bar where he got his hands on some useful information about Blackbeard's whereabouts. 

Teach could be found in the next island. Lucky for him, Thatch had awoken. So Ace would just beat him near to death and leave him there, letting fate decide whether he should live. Fair enough.

"Ace, you should return to Moby Dick with me, yoi."Ace lifted his head, only to find a certain pineapple beside him.

"I'm this close to Teach. Sorry, Marco, I can't just give up here." Staring at the first division commander, Ace reasoned.

"Not even when Garp is on Moby Dick? "

Ace found words hard to express his feelings. What makes Marco think he wouldn't run at the first scent of that old geezer?

"He has Luffy as company who-----" 

Ace thought: 'Nice try. However, I already met him'. He waited for Marco to finish. Boy, wasn't it a pregnant pause.

"-----is pregnant, and you are the father, yoi."

"If that's what you've got in stash for April Fool's day, I feel bad for you, hahaha." Ace burst into laughter, almost doubling himself over.

Marco deadpanned:"So you want to play dumb. I have to say you don't strike me like that kind of guy, yoi."

"Man plus man euqals no baby. Though I'm not sure about the reproduction of you birds, human's does work like that."

"So, no denial of the fact that you had sex with your little brother, yoi." Marco looked him in the eyes.

Ace stiffend.

Now, thinking about it, how in hell did Marco know about their encounter, thus pulling the prank. Did he send out birds to watch him? No,no, he is not that creepy. Then, only one explanation left…

"No, no way, I mean, he is……I'm……" Ace threw his hands in the air, desperately trying to get a hold of his sanity.

Marco sentenced him to death:"Ever heard of male carrier, yoi."

"Mom, there is a man being held upside-down by a big blue bird in the air!" A little girl exclaimed down below.

"I'd like to give credit for your imagination, baby girl." The mother said with a fond smile, but clearly she didn't trust her daughter's words.

Can't blame her. As eccentric as the Grand Line went, this was not a everyday sight.

"Hey, you know what, I really want to upgrade my seat." Being fed up with viewing the world from a whole different angle, Ace cracked.

Marco gave him an eyeroll, which was very impressive, considering the size of his current form:"This suits a brotherfucker well, don't you think?"

Marco was burning on the flame of anger, which was more figurative than the blue one literally wrapped around him.

He was indignant with a reason. Due to Ace's non-stop rant about his baby brother, Marco had become one of the self-assigned big brothers of Luffy, despite he had yet met the kid.

It's older brothers' duty to eliminate everyone who dared even try to ruin their little brother's innocence. Too bad, there was a traitor among themselves.

Becoming aware of Marco's ever-worsening anger, a shiver of fear run down Ace's spine. The good thing was that pops had this unbreakable rule: no killing each other among crew, which happened to be the last thing stopped Marco from eliminating him, making Ace love pops even more, if that's possible.

Of course, Ace didn't know Luffy was a carrier either. Had he known, he would…he would at least use protection back in Alabasta. Internally despising himself, Ace knew he let his desire take the best of him. While, three years seperation could do that to a man.

"Just so you know, the whole thing was consensual." Ace said all of a sudden.

Marco was not impressed:"It definitely was. You may be a traitor of big brother duty, but absolutely above taking advantage of someone. "

Ace chuckled, the sliver of nervousness evaporated: "Better tell you something about the beginning of our relationship."

Three years ago.

Ace would set sail in pursuit of his dream in a few days. Though who's he kidding, if he said this had nothing to do with running away from his baby brother.

It's so ironic to think about. 

After the accident that took Sabo away, Ace was bent on ensuring his brother's happiness and safety. 

While, from outsider's view, Luffy seemed to have done nothing but keep being the fool he was. However, only Ace knew how many times a sound asleep Luffy next to him kept the anger and hate that woke him up at night in check.

Luffy needed him, and Ace would be damned if that's not vice versa. He would give up everything to spend every second of his life with Luffy, until puberty ruined it all.

Suddenly, everything about Luffy was not the same to Ace. He became super aware of the other's sweet voice, soft skin, delicate ankles and so on. In a word, Luffy's every movement was a turn-on for Ace. The way he licked popsicles, or how Ace could have a thorough view through the collar of Luffy's baggy T-shirt when he perched on Ace's lap, they were a chronical death for him.

Terribly troubled, Ace even turned to books to solve his problems. According to a dust-collecting book, it's normal for teenage boys to be constantly horny.

Hell, it's even okay to be aroused by a tree hole. The only question was that Ace did not get turned on by something like a tree hole or anyone other than Luffy, to be accurate. It almost felt like Luffy had monopoly of his down there salutes.

Another book gave him the answer and sent him into infinite horror. This long-term sexual attraction one felt towards a particular person stood for crush or, dare he say, love.

That night, Ace had a dream where he and Luffy were standing in a church. Their faces were closer and closer, drawn by something invisible. Ace could feel Luffy's breath brush against his cheek like a feather, making him itchy deep inside his soul.

They would share a kiss only if Sabo didn't come out of nowhere, holding Ace's collar and yelling at him:"ACE! THIS IS HOW YOU TAKR CARE OF OUR LITTLE BROTHER?"

To make things worse, Luffy who shared an intimate moment with Ace seconds ago scowled at him. His knitted brows and freezing eyes spelled disgust:"Ah, so Ace has these feelings for me. Sorry, we can't be brothers any more."

Breathing became such a laborious thing for Ace, and Sabo's tightening hold was not the sole cause of it. Ace woke up with sweat all over his forehead and Luffy's arms wrapping around his neck. 

Ace made a decision overnight.

He started to avoid Luffy. Sure they still did their daily drills together, but anything involved skin against skin and dangerous proximity was off-limits. God, the look on Luffy's face made Ace feel like an asshole who kicked a puppy, and what he did is refuse Luffy when he tried to sit on his lap.

Had he mentioned that he have to make Luffy sleep in his own bed? That's hard. Luffy was not thrilled, pleading to sleep with Ace like they always did. He couldn't bring himself to tell Luffy who had those innocent eyes that he want to sleep with him too, but in a lewd way.

Life was like chewing gum with too long a service, plain and boring ever since that. But Ace managed to pull through, though what he felt for Luffy remained if not thrived in spite of his suppression.

Another night with the empty home. Ace could hardly rein in his wild thoughts.

Recently Luffy started to hide from him, claiming to hang out with Makino. Maybe, his dense head finally realised he was a teenager now, and threw him a bunch of adolescents' issues, or Luffy had caught one of Ace's swift glances at him and decoded it……

Bitterness ran wild in his mouth, and Ace was not sure whether it's fortunate or not that this was the last night before he left. Is it the end of the ordeal or the beginning of a new one? He was yet to know.

To say Ace was relieved when he spotted his brother among people seeing him off would be a huge understatement. Ace felt like he was allowed to breathe for the first time in days.

"Ace, take this." Luffy handed him a box, which was apparently wrapped by him, judging by the humble look. He also gifted him with spell-like words:"So, see you three years later, Ace."

It must be a spell full of magic. Otherwise, how to explain the way it made Ace drenched with joy. Obediently, Ace took the box with slightly shaking hands. Who could blame him, for what the little box contained was more of a assurance of their brotherhood than a simple present.

At least, they can still be brothers after all. Ace should be content, right? 

Before the wind filled his sail, Ace turned his head to face the island on which he grew up. Though, it's Luffy that he set his eyes on at the last moment. It didn't come as a surprise to him, but confirmation. 

What came in his mind when talking about home? Luffy.

With the wind in his favor, Ace's boat was carried more and more away from the shore. He couldn't make out Luffy's smile, and the straw hat on his head was indistinguishable soon after.

As if on cue, his narcolepsy decided to kick in, which Ace considered a blessing (at this moment though).

When he came to, stars were scattered above him. Without a sense of where he was and what to do, Ace idly glanced over the entire floor of his boat, and it's a really fast movement because it didn't have much to begin with.

Something caught his eyes. He lifted it to see it's the present from Luffy, unwrapping the small present, and its content was revealed to be a card, which was expected due to its size.

Did it make Ace a hentai if he could caught the smell of his brother from the letter? It's what hardly a day had done to him, and Ace started to question his chances of survival.

Being unfolded, the card gave everything it had to offer. It has colorful paintings and they were drawn with crayons, a fact that made Ace almost coo. His brother was still a baby!

There was a stick figure with a yellow bowl or something on its head, and another stick figure stood by his side with something like mud spots on his face. They were hand in hand. 

It took a moment for him to realise what/who they are. And the words beneath them were something that gave him a heart attack.

"Ace, I love you in a rolen(scratch that) romantic way. （A painting of smiling face）It feels good to finally say this. I've spent weeks trying to find a way to do so. But I failed. So I take Makino's advice to write you a letter. Maybe it's better this way. I mean you've got three years to decide your answer. Either way, I look forward to meeting you in the future. We are brothers no matter what, right? PS: Makino suggests that I give you the letter along with some meat, but I eat them all shishishihi."

"WHAT!"

Ace let out a extremely high-pitched cry. Meanwhile, some knocked-out seakings floated on water surface. It's just Ace's luck that he ignited his Conqueror's Haki, to no avail. Haki or not, in no way could he wipe out the unknown distance between him and his brother, giving Luffy the answer he had in mind all along.

"LUFFY!" 

With that cry, another couple of unconscious seakings appeared belly up, surrounding the little boat.

Let's just say Ace couldn't find it in himself to fall asleep, and the seakings there had the worst night ever.

Marco couldn't help laughing. As a doctor, he was full aware that the chance of someone laughing themselves to death was very slim. But now he questioned himself: will the outcome differ when you're a bird, while laughing, of course.

Ace was resigned to all of this, sighing with nostalgia:"In hindsight, that is actually not that bad. I mean, if we managed to enter into a relationship back then, wouldn't Luffy be a pregnant 14 years old? Then I would want death myself, aside from the geezer's Love of Fist."

"Speaking of which, how did pops react to this? Was he disappointed? "

"Pops being pops, I couldn't figure out his thoughts. But 'disappointed' it's not the word I will use to describe him, 'surprised', maybe, yoi."

Couple of hours ago.

Whitebeard mechanically had a swig of his sake, while none of the nurses was gonna stop him. You could tell from their expressions that they would appreciate a drink themselves, which was a thought shared by the present commanders.

Having Ace as their little brother, they all had their fair share of dealing with people or more accurately, victims demanding their troublemaker of a brother. Nonetheless, nothing had prepared them for this.

When Garp the Fist showed up on a ship with some freaking cannonballs in hands, they feared that they would be blown up by him. But the fate apparently had something else in store for them, and it's their minds that got blown up by the news Garp brought along.

The strongest man in the world obviously had the strongest adaptability, being the first to say something:"So this brat who used to be Ace's sworn little brother is now his lover and pregnant."

"Yep." Strangely being the most carefree person in this room despite all the talks were centered on him, Luffy confirmed, busying himself with picking his nose.

Mirroring his grandson's movements, though with grimness, Garp flicking his pointer, which had been buried so deep in his nose that some believed it's got whatever left of his brains on itself:" So you know I have a very sensible reason to demand Ace."

"I will send Marco to pick him up."

Marco nodded his head in acknowledgement, and subtly took a look at the kid, while that word was disturbing in this context, so he would settle on teen. It's a common belief that Marco was a master of Observation Haki, but even he couldn't see a soon-to-be parent in Luffy.

While, he would make sure to give Ace a piece of his mind. Marco started to leave, hand on the knob when Whitebeard said casually:"Oi, Garp, you don't plan to castrate Ace, do you? I'd like for him to be my son."

When they arrived at Moby Dick, the sky was dark and the deck was empty except one vice admiral who turned around to look at them, the very embodiment of the devil itself. Despite still being angry at Ace, Marco gave him a sympathetic look before making himself scarce. 

Ace found himself at a loss as to what to do. Luffy and he didn't want to announce their new relationship to everyone who would listen, just went with it. But the further reason was that Ace didn't know how to break the news to Garp. Hey, your grandsons decided it's a good idea to improve their relationship to the next level. So congratulations, we were a even closer family.

What if Garp disapproved the thing between them? Ace was haunted by the most likely assumption, cause he knew. Even leave his lineage out of this, he was hardly a good match for Luffy who was pure and vibrant like sun on earth, while Ace was someone had darkness wrapped around himself all the time……

And the present situation was definitely the worst way ever for Garp to learn about the affair. It's not that they could just shrug it off and pretend like nothing happened, because the evidence that everything happened was right there, in Luffy's belly.

Lost in his thoughts, when Ace heard Garp called his name and showed him to join his grandpa (a fact Ace accepted for a while, as much as he refused to display, the old geezer was his grandpa either way)by the railing, he internally gave Garp a thumb up. After all, what's a better approach to get rid of Devil Fruit users than throw them overboard.

Against his better jugdement, he came over to lean on the railing next to Garp. The vice admiral stretched one of his arms and did nothing more than gave the freckled man's shoulder a tap.

"Time surely flies. I just move my eyes for a second and you've grown up, making me a great grandpa." Was it just Ace, or was there really something as pride in his voice?

Ace had to ask. "So you are not against the idea that we're together? As in no intention to separate us or make me kick the bucket." 

Garp shouted indignantly:"Ace,it's not nice of you to think your grandpa is that evil." Ace just stared at him until he gave up:"Fine, I might think about that for a liiiiiiiittle, but…"

His face softened in a way that no one had expected from Garp the Fist:"I actually couldn't picture you with anyone but each other. "

Ace could deal with anything thorwn at him, but feelings were another story. He had been silent for minutes before a question poped out of his head and mouth:"Do you think we'll be happy together? What if I'm not good enough for him?"

Ace cursed under his breath. Good, now he felt like a child again, helplessly waiting for an answer. And the answer Garp gave him was almost the same:"You have to carry on to know for sure."

None of them talked after that. Wind woven with the smell of sea swept from Garp's white hair to Ace's black one, and if there was any moisture on his face, it must be the dew.

Ace turned around to leave before he remembered something:"By the way, I notice your ship out there has some damage. Did you get into a fight with someone?"

"On our way here, someone self-claimed to be Blackbeard jumped out of nowhere, shouting about defeating Luffy and turning him in. Luffy was not fitted for that, so as every grandpa would do, I got on deck to give him a punch and a one-way ticket to Impel Down. "

Ace flinched at the implication, but Teach deserved it, so this was something worth giving a toast to.

Luffy was sleeping in his room on his bed, which satisfied Ace's stupid possessiveness. He lifted the covers a little to slide in, having Luffy in his arms like the good old times.

Luffy naturally nuzzled against his neck, mumbling:"Ace, you're back." Putting his chin on Luffy's head, Ace was drowned in all the familiarity, and he vaguely felt the call of dreamland, but he had to figure the things out.

"Luffy, I'm sorry."

"What for? "

"The accidental pregnancy."

It was all it took to make Luffy fully awake, then he looked up with a smile that only could be accomplished by a rubberman:"No need to say sorry, not everything comes with an accident is bad. "

"But Luffy, you're too young to be a parent." 

"I'm old enough to set sail, be a captain and kick bad guys' asses. Why not become a parent? "

Sometimes, Luffy did know his way around words. Ace sighed, and the biggest fear buried in his heart showed itself. During pregnancy, there was a very thin line between birth and death, and Ace was the very proof of that.

It's not until Luffy's words startled him that Ace realised he said his thoughts aloud:"Everything has a risk. And it's in human's nature to avoid risk, but once in a while, people will ignore it, because what they are doing is worth it."

To emphasize his point, Luffy took Ace's hand to put it on his stomach that was still flat:"This is worth it and you're worth it too, Ace. I am very excited about the whole thing, because our baby will be the child of the Pirate King too. But we are able to be by their side when they grow up, so they won't be sad. It's like rewriting the history shishishishi! "

The insight of Luffy made Ace speechless, and all the emotions that erupted in his chest left him giddy. Right now, words couldn't express his feelings, so he chose the only thing could. He kissed Luffy, using lips and fingers running through his hair to tell the depth of his love.

This was three days before Ace asked Luffy to marry him with a ring by the courtesy of Jozu, and ten days before their wedding day.

The family reunion before the wedding was going smoothly with the sign that Ace made it out alive. It was decided that both Shanks and Dragon would walk Luffy down the aisle, much to the former's ecstasy and the latter's chagrin.

But to be fair, as a father that Luffy recently knew he had, Dragon should expect it. He showed up with that badass face and took their relationship in stride, crisply giving the permission which they did not need and blessing.

While Shanks' attitude had had some drastic changes. When he arrived, he acted so maliciously that if Ace had disappeared that night, he would have been the number one suspect. But after a private conversation with Whitebeard, Shanks quitted being hostile against Ace. And Ace really didn't want to think about the meaning behind those complicated looks Shanks gave him.

After all, everyone was happy, but the same couldn't be said about Little Oars Jr. who was too big to fit in the church, so he had to lay down outside and watched the ritual through the door.

Ace was wary of Dragon's slight worried expression. He approach his father-in-law before the wedding started, asking if something was wrong. It didn't hurt to be careful on the second most important day of his life. (Btw, the most important day was when he met Luffy.)

"Nothing, it's just my Chief of Staff has fallen ill and become bedridden upon arriving, and I'm worried about him."

Now, the ritual was coming to an end. After exchanging rings (also by the courtesy of Jozu), the couple were gonna seal it with a kiss. Cupping Luffy's face, Ace brought their lips closer and closer, but came to a halt when there was barely an inch between them.

Someone got hold of his collar and yelled at him from behind:"ACE! THIS IS HOW YOU TAKE CARE OF OUR LITTLE BROTHER?"

Ace was hit by the feeling of dejavu. Luffy's eyes widened, and it turned out that's actually possible.

For the guests, this must look like a scene out of cliche romantic movies when the man in blue stopped the groom in the process of kissing his husband, and the other groom became tearful before jumped into the said man's arms.

After some heated exchange of words, everything was peaceful, or who was I kidding?

"So you are alive in the past ten years, and you don't even bother to call us, YOU ASSHOLE! "

"I said I had amnesia! And who said we should protect our little brother from perverts, oh, it's you, YOU PERVERT!" 

"You think you have the right to judge me, MR.OBLIVIOUS? We thought you was dead and even decided to name our baby after you if it's a boy! "

"I'm flattered, wait, YOU'VE GOT LUFFY PREGNANT!!"


End file.
